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|
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2020 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <wallet/bdb.h>
#include <wallet/db.h>
#include <util/strencodings.h>
#include <util/translation.h>
#include <stdint.h>
#ifndef WIN32
#include <sys/stat.h>
#endif
namespace {
//! Make sure database has a unique fileid within the environment. If it
//! doesn't, throw an error. BDB caches do not work properly when more than one
//! open database has the same fileid (values written to one database may show
//! up in reads to other databases).
//!
//! BerkeleyDB generates unique fileids by default
//! (https://docs.oracle.com/cd/E17275_01/html/programmer_reference/program_copy.html),
//! so bitcoin should never create different databases with the same fileid, but
//! this error can be triggered if users manually copy database files.
void CheckUniqueFileid(const BerkeleyEnvironment& env, const std::string& filename, Db& db, WalletDatabaseFileId& fileid)
{
if (env.IsMock()) return;
int ret = db.get_mpf()->get_fileid(fileid.value);
if (ret != 0) {
throw std::runtime_error(strprintf("BerkeleyBatch: Can't open database %s (get_fileid failed with %d)", filename, ret));
}
for (const auto& item : env.m_fileids) {
if (fileid == item.second && &fileid != &item.second) {
throw std::runtime_error(strprintf("BerkeleyBatch: Can't open database %s (duplicates fileid %s from %s)", filename,
HexStr(std::begin(item.second.value), std::end(item.second.value)), item.first));
}
}
}
RecursiveMutex cs_db;
std::map<std::string, std::weak_ptr<BerkeleyEnvironment>> g_dbenvs GUARDED_BY(cs_db); //!< Map from directory name to db environment.
} // namespace
bool WalletDatabaseFileId::operator==(const WalletDatabaseFileId& rhs) const
{
return memcmp(value, &rhs.value, sizeof(value)) == 0;
}
bool IsBDBWalletLoaded(const fs::path& wallet_path)
{
fs::path env_directory;
std::string database_filename;
SplitWalletPath(wallet_path, env_directory, database_filename);
LOCK(cs_db);
auto env = g_dbenvs.find(env_directory.string());
if (env == g_dbenvs.end()) return false;
auto database = env->second.lock();
return database && database->IsDatabaseLoaded(database_filename);
}
/**
* @param[in] wallet_path Path to wallet directory. Or (for backwards compatibility only) a path to a berkeley btree data file inside a wallet directory.
* @param[out] database_filename Filename of berkeley btree data file inside the wallet directory.
* @return A shared pointer to the BerkeleyEnvironment object for the wallet directory, never empty because ~BerkeleyEnvironment
* erases the weak pointer from the g_dbenvs map.
* @post A new BerkeleyEnvironment weak pointer is inserted into g_dbenvs if the directory path key was not already in the map.
*/
std::shared_ptr<BerkeleyEnvironment> GetWalletEnv(const fs::path& wallet_path, std::string& database_filename)
{
fs::path env_directory;
SplitWalletPath(wallet_path, env_directory, database_filename);
LOCK(cs_db);
auto inserted = g_dbenvs.emplace(env_directory.string(), std::weak_ptr<BerkeleyEnvironment>());
if (inserted.second) {
auto env = std::make_shared<BerkeleyEnvironment>(env_directory.string());
inserted.first->second = env;
return env;
}
return inserted.first->second.lock();
}
//
// BerkeleyBatch
//
void BerkeleyEnvironment::Close()
{
if (!fDbEnvInit)
return;
fDbEnvInit = false;
for (auto& db : m_databases) {
BerkeleyDatabase& database = db.second.get();
assert(database.m_refcount <= 0);
if (database.m_db) {
database.m_db->close(0);
database.m_db.reset();
}
}
FILE* error_file = nullptr;
dbenv->get_errfile(&error_file);
int ret = dbenv->close(0);
if (ret != 0)
LogPrintf("BerkeleyEnvironment::Close: Error %d closing database environment: %s\n", ret, DbEnv::strerror(ret));
if (!fMockDb)
DbEnv((u_int32_t)0).remove(strPath.c_str(), 0);
if (error_file) fclose(error_file);
UnlockDirectory(strPath, ".walletlock");
}
void BerkeleyEnvironment::Reset()
{
dbenv.reset(new DbEnv(DB_CXX_NO_EXCEPTIONS));
fDbEnvInit = false;
fMockDb = false;
}
BerkeleyEnvironment::BerkeleyEnvironment(const fs::path& dir_path) : strPath(dir_path.string())
{
Reset();
}
BerkeleyEnvironment::~BerkeleyEnvironment()
{
LOCK(cs_db);
g_dbenvs.erase(strPath);
Close();
}
bool BerkeleyEnvironment::Open(bilingual_str& err)
{
if (fDbEnvInit) {
return true;
}
fs::path pathIn = strPath;
TryCreateDirectories(pathIn);
if (!LockDirectory(pathIn, ".walletlock")) {
LogPrintf("Cannot obtain a lock on wallet directory %s. Another instance of bitcoin may be using it.\n", strPath);
err = strprintf(_("Error initializing wallet database environment %s!"), Directory());
return false;
}
fs::path pathLogDir = pathIn / "database";
TryCreateDirectories(pathLogDir);
fs::path pathErrorFile = pathIn / "db.log";
LogPrintf("BerkeleyEnvironment::Open: LogDir=%s ErrorFile=%s\n", pathLogDir.string(), pathErrorFile.string());
unsigned int nEnvFlags = 0;
if (gArgs.GetBoolArg("-privdb", DEFAULT_WALLET_PRIVDB))
nEnvFlags |= DB_PRIVATE;
dbenv->set_lg_dir(pathLogDir.string().c_str());
dbenv->set_cachesize(0, 0x100000, 1); // 1 MiB should be enough for just the wallet
dbenv->set_lg_bsize(0x10000);
dbenv->set_lg_max(1048576);
dbenv->set_lk_max_locks(40000);
dbenv->set_lk_max_objects(40000);
dbenv->set_errfile(fsbridge::fopen(pathErrorFile, "a")); /// debug
dbenv->set_flags(DB_AUTO_COMMIT, 1);
dbenv->set_flags(DB_TXN_WRITE_NOSYNC, 1);
dbenv->log_set_config(DB_LOG_AUTO_REMOVE, 1);
int ret = dbenv->open(strPath.c_str(),
DB_CREATE |
DB_INIT_LOCK |
DB_INIT_LOG |
DB_INIT_MPOOL |
DB_INIT_TXN |
DB_THREAD |
DB_RECOVER |
nEnvFlags,
S_IRUSR | S_IWUSR);
if (ret != 0) {
LogPrintf("BerkeleyEnvironment::Open: Error %d opening database environment: %s\n", ret, DbEnv::strerror(ret));
int ret2 = dbenv->close(0);
if (ret2 != 0) {
LogPrintf("BerkeleyEnvironment::Open: Error %d closing failed database environment: %s\n", ret2, DbEnv::strerror(ret2));
}
Reset();
err = strprintf(_("Error initializing wallet database environment %s!"), Directory());
if (ret == DB_RUNRECOVERY) {
err += Untranslated(" ") + _("This error could occur if this wallet was not shutdown cleanly and was last loaded using a build with a newer version of Berkeley DB. If so, please use the software that last loaded this wallet");
}
return false;
}
fDbEnvInit = true;
fMockDb = false;
return true;
}
//! Construct an in-memory mock Berkeley environment for testing
BerkeleyEnvironment::BerkeleyEnvironment()
{
Reset();
LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::MakeMock\n");
dbenv->set_cachesize(1, 0, 1);
dbenv->set_lg_bsize(10485760 * 4);
dbenv->set_lg_max(10485760);
dbenv->set_lk_max_locks(10000);
dbenv->set_lk_max_objects(10000);
dbenv->set_flags(DB_AUTO_COMMIT, 1);
dbenv->log_set_config(DB_LOG_IN_MEMORY, 1);
int ret = dbenv->open(nullptr,
DB_CREATE |
DB_INIT_LOCK |
DB_INIT_LOG |
DB_INIT_MPOOL |
DB_INIT_TXN |
DB_THREAD |
DB_PRIVATE,
S_IRUSR | S_IWUSR);
if (ret > 0) {
throw std::runtime_error(strprintf("BerkeleyEnvironment::MakeMock: Error %d opening database environment.", ret));
}
fDbEnvInit = true;
fMockDb = true;
}
BerkeleyBatch::SafeDbt::SafeDbt()
{
m_dbt.set_flags(DB_DBT_MALLOC);
}
BerkeleyBatch::SafeDbt::SafeDbt(void* data, size_t size)
: m_dbt(data, size)
{
}
BerkeleyBatch::SafeDbt::~SafeDbt()
{
if (m_dbt.get_data() != nullptr) {
// Clear memory, e.g. in case it was a private key
memory_cleanse(m_dbt.get_data(), m_dbt.get_size());
// under DB_DBT_MALLOC, data is malloced by the Dbt, but must be
// freed by the caller.
// https://docs.oracle.com/cd/E17275_01/html/api_reference/C/dbt.html
if (m_dbt.get_flags() & DB_DBT_MALLOC) {
free(m_dbt.get_data());
}
}
}
const void* BerkeleyBatch::SafeDbt::get_data() const
{
return m_dbt.get_data();
}
u_int32_t BerkeleyBatch::SafeDbt::get_size() const
{
return m_dbt.get_size();
}
BerkeleyBatch::SafeDbt::operator Dbt*()
{
return &m_dbt;
}
bool BerkeleyDatabase::Verify(bilingual_str& errorStr)
{
fs::path walletDir = env->Directory();
fs::path file_path = walletDir / strFile;
LogPrintf("Using BerkeleyDB version %s\n", BerkeleyDatabaseVersion());
LogPrintf("Using wallet %s\n", file_path.string());
if (!env->Open(errorStr)) {
return false;
}
if (fs::exists(file_path))
{
assert(m_refcount == 0);
Db db(env->dbenv.get(), 0);
int result = db.verify(strFile.c_str(), nullptr, nullptr, 0);
if (result != 0) {
errorStr = strprintf(_("%s corrupt. Try using the wallet tool bitcoin-wallet to salvage or restoring a backup."), file_path);
return false;
}
}
// also return true if files does not exists
return true;
}
void BerkeleyEnvironment::CheckpointLSN(const std::string& strFile)
{
dbenv->txn_checkpoint(0, 0, 0);
if (fMockDb)
return;
dbenv->lsn_reset(strFile.c_str(), 0);
}
BerkeleyDatabase::~BerkeleyDatabase()
{
if (env) {
LOCK(cs_db);
size_t erased = env->m_databases.erase(strFile);
assert(erased == 1);
env->m_fileids.erase(strFile);
}
}
BerkeleyBatch::BerkeleyBatch(BerkeleyDatabase& database, const char* pszMode, bool fFlushOnCloseIn) : pdb(nullptr), activeTxn(nullptr), m_cursor(nullptr), m_database(database)
{
database.AddRef();
database.Open(pszMode);
fReadOnly = (!strchr(pszMode, '+') && !strchr(pszMode, 'w'));
fFlushOnClose = fFlushOnCloseIn;
env = database.env.get();
pdb = database.m_db.get();
strFile = database.strFile;
bool fCreate = strchr(pszMode, 'c') != nullptr;
if (fCreate && !Exists(std::string("version"))) {
bool fTmp = fReadOnly;
fReadOnly = false;
Write(std::string("version"), CLIENT_VERSION);
fReadOnly = fTmp;
}
}
void BerkeleyDatabase::Open(const char* pszMode)
{
if (IsDummy()){
return;
}
bool fCreate = strchr(pszMode, 'c') != nullptr;
unsigned int nFlags = DB_THREAD;
if (fCreate)
nFlags |= DB_CREATE;
{
LOCK(cs_db);
bilingual_str open_err;
if (!env->Open(open_err))
throw std::runtime_error("BerkeleyDatabase: Failed to open database environment.");
if (m_db == nullptr) {
int ret;
std::unique_ptr<Db> pdb_temp = MakeUnique<Db>(env->dbenv.get(), 0);
bool fMockDb = env->IsMock();
if (fMockDb) {
DbMpoolFile* mpf = pdb_temp->get_mpf();
ret = mpf->set_flags(DB_MPOOL_NOFILE, 1);
if (ret != 0) {
throw std::runtime_error(strprintf("BerkeleyDatabase: Failed to configure for no temp file backing for database %s", strFile));
}
}
ret = pdb_temp->open(nullptr, // Txn pointer
fMockDb ? nullptr : strFile.c_str(), // Filename
fMockDb ? strFile.c_str() : "main", // Logical db name
DB_BTREE, // Database type
nFlags, // Flags
0);
if (ret != 0) {
throw std::runtime_error(strprintf("BerkeleyDatabase: Error %d, can't open database %s", ret, strFile));
}
// Call CheckUniqueFileid on the containing BDB environment to
// avoid BDB data consistency bugs that happen when different data
// files in the same environment have the same fileid.
//
// Also call CheckUniqueFileid on all the other g_dbenvs to prevent
// bitcoin from opening the same data file through another
// environment when the file is referenced through equivalent but
// not obviously identical symlinked or hard linked or bind mounted
// paths. In the future a more relaxed check for equal inode and
// device ids could be done instead, which would allow opening
// different backup copies of a wallet at the same time. Maybe even
// more ideally, an exclusive lock for accessing the database could
// be implemented, so no equality checks are needed at all. (Newer
// versions of BDB have an set_lk_exclusive method for this
// purpose, but the older version we use does not.)
for (const auto& env : g_dbenvs) {
CheckUniqueFileid(*env.second.lock().get(), strFile, *pdb_temp, this->env->m_fileids[strFile]);
}
m_db.reset(pdb_temp.release());
}
}
}
void BerkeleyBatch::Flush()
{
if (activeTxn)
return;
// Flush database activity from memory pool to disk log
unsigned int nMinutes = 0;
if (fReadOnly)
nMinutes = 1;
if (env) { // env is nullptr for dummy databases (i.e. in tests). Don't actually flush if env is nullptr so we don't segfault
env->dbenv->txn_checkpoint(nMinutes ? gArgs.GetArg("-dblogsize", DEFAULT_WALLET_DBLOGSIZE) * 1024 : 0, nMinutes, 0);
}
}
void BerkeleyDatabase::IncrementUpdateCounter()
{
++nUpdateCounter;
}
BerkeleyBatch::~BerkeleyBatch()
{
Close();
m_database.RemoveRef();
}
void BerkeleyBatch::Close()
{
if (!pdb)
return;
if (activeTxn)
activeTxn->abort();
activeTxn = nullptr;
pdb = nullptr;
CloseCursor();
if (fFlushOnClose)
Flush();
}
void BerkeleyEnvironment::CloseDb(const std::string& strFile)
{
{
LOCK(cs_db);
auto it = m_databases.find(strFile);
assert(it != m_databases.end());
BerkeleyDatabase& database = it->second.get();
if (database.m_db) {
// Close the database handle
database.m_db->close(0);
database.m_db.reset();
}
}
}
void BerkeleyEnvironment::ReloadDbEnv()
{
// Make sure that no Db's are in use
AssertLockNotHeld(cs_db);
std::unique_lock<RecursiveMutex> lock(cs_db);
m_db_in_use.wait(lock, [this](){
for (auto& db : m_databases) {
if (db.second.get().m_refcount > 0) return false;
}
return true;
});
std::vector<std::string> filenames;
for (auto it : m_databases) {
filenames.push_back(it.first);
}
// Close the individual Db's
for (const std::string& filename : filenames) {
CloseDb(filename);
}
// Reset the environment
Flush(true); // This will flush and close the environment
Reset();
bilingual_str open_err;
Open(open_err);
}
bool BerkeleyDatabase::Rewrite(const char* pszSkip)
{
if (IsDummy()) {
return true;
}
while (true) {
{
LOCK(cs_db);
if (m_refcount <= 0) {
// Flush log data to the dat file
env->CloseDb(strFile);
env->CheckpointLSN(strFile);
m_refcount = -1;
bool fSuccess = true;
LogPrintf("BerkeleyBatch::Rewrite: Rewriting %s...\n", strFile);
std::string strFileRes = strFile + ".rewrite";
{ // surround usage of db with extra {}
BerkeleyBatch db(*this, "r");
std::unique_ptr<Db> pdbCopy = MakeUnique<Db>(env->dbenv.get(), 0);
int ret = pdbCopy->open(nullptr, // Txn pointer
strFileRes.c_str(), // Filename
"main", // Logical db name
DB_BTREE, // Database type
DB_CREATE, // Flags
0);
if (ret > 0) {
LogPrintf("BerkeleyBatch::Rewrite: Can't create database file %s\n", strFileRes);
fSuccess = false;
}
if (db.StartCursor()) {
while (fSuccess) {
CDataStream ssKey(SER_DISK, CLIENT_VERSION);
CDataStream ssValue(SER_DISK, CLIENT_VERSION);
bool complete;
bool ret1 = db.ReadAtCursor(ssKey, ssValue, complete);
if (complete) {
break;
} else if (!ret1) {
fSuccess = false;
break;
}
if (pszSkip &&
strncmp(ssKey.data(), pszSkip, std::min(ssKey.size(), strlen(pszSkip))) == 0)
continue;
if (strncmp(ssKey.data(), "\x07version", 8) == 0) {
// Update version:
ssValue.clear();
ssValue << CLIENT_VERSION;
}
Dbt datKey(ssKey.data(), ssKey.size());
Dbt datValue(ssValue.data(), ssValue.size());
int ret2 = pdbCopy->put(nullptr, &datKey, &datValue, DB_NOOVERWRITE);
if (ret2 > 0)
fSuccess = false;
}
db.CloseCursor();
}
if (fSuccess) {
db.Close();
env->CloseDb(strFile);
if (pdbCopy->close(0))
fSuccess = false;
} else {
pdbCopy->close(0);
}
}
if (fSuccess) {
Db dbA(env->dbenv.get(), 0);
if (dbA.remove(strFile.c_str(), nullptr, 0))
fSuccess = false;
Db dbB(env->dbenv.get(), 0);
if (dbB.rename(strFileRes.c_str(), nullptr, strFile.c_str(), 0))
fSuccess = false;
}
if (!fSuccess)
LogPrintf("BerkeleyBatch::Rewrite: Failed to rewrite database file %s\n", strFileRes);
return fSuccess;
}
}
UninterruptibleSleep(std::chrono::milliseconds{100});
}
}
void BerkeleyEnvironment::Flush(bool fShutdown)
{
int64_t nStart = GetTimeMillis();
// Flush log data to the actual data file on all files that are not in use
LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: [%s] Flush(%s)%s\n", strPath, fShutdown ? "true" : "false", fDbEnvInit ? "" : " database not started");
if (!fDbEnvInit)
return;
{
LOCK(cs_db);
bool no_dbs_accessed = true;
for (auto& db_it : m_databases) {
std::string strFile = db_it.first;
int nRefCount = db_it.second.get().m_refcount;
if (nRefCount < 0) continue;
LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: Flushing %s (refcount = %d)...\n", strFile, nRefCount);
if (nRefCount == 0) {
// Move log data to the dat file
CloseDb(strFile);
LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: %s checkpoint\n", strFile);
dbenv->txn_checkpoint(0, 0, 0);
LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: %s detach\n", strFile);
if (!fMockDb)
dbenv->lsn_reset(strFile.c_str(), 0);
LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: %s closed\n", strFile);
nRefCount = -1;
} else {
no_dbs_accessed = false;
}
}
LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: Flush(%s)%s took %15dms\n", fShutdown ? "true" : "false", fDbEnvInit ? "" : " database not started", GetTimeMillis() - nStart);
if (fShutdown) {
char** listp;
if (no_dbs_accessed) {
dbenv->log_archive(&listp, DB_ARCH_REMOVE);
Close();
if (!fMockDb) {
fs::remove_all(fs::path(strPath) / "database");
}
}
}
}
}
bool BerkeleyDatabase::PeriodicFlush()
{
// There's nothing to do for dummy databases. Return true.
if (IsDummy()) return true;
// Don't flush if we can't acquire the lock.
TRY_LOCK(cs_db, lockDb);
if (!lockDb) return false;
// Don't flush if any databases are in use
for (auto& it : env->m_databases) {
if (it.second.get().m_refcount > 0) return false;
}
// Don't flush if there haven't been any batch writes for this database.
if (m_refcount < 0) return false;
LogPrint(BCLog::WALLETDB, "Flushing %s\n", strFile);
int64_t nStart = GetTimeMillis();
// Flush wallet file so it's self contained
env->CloseDb(strFile);
env->CheckpointLSN(strFile);
m_refcount = -1;
LogPrint(BCLog::WALLETDB, "Flushed %s %dms\n", strFile, GetTimeMillis() - nStart);
return true;
}
bool BerkeleyDatabase::Backup(const std::string& strDest) const
{
if (IsDummy()) {
return false;
}
while (true)
{
{
LOCK(cs_db);
if (m_refcount <= 0)
{
// Flush log data to the dat file
env->CloseDb(strFile);
env->CheckpointLSN(strFile);
// Copy wallet file
fs::path pathSrc = env->Directory() / strFile;
fs::path pathDest(strDest);
if (fs::is_directory(pathDest))
pathDest /= strFile;
try {
if (fs::equivalent(pathSrc, pathDest)) {
LogPrintf("cannot backup to wallet source file %s\n", pathDest.string());
return false;
}
fs::copy_file(pathSrc, pathDest, fs::copy_option::overwrite_if_exists);
LogPrintf("copied %s to %s\n", strFile, pathDest.string());
return true;
} catch (const fs::filesystem_error& e) {
LogPrintf("error copying %s to %s - %s\n", strFile, pathDest.string(), fsbridge::get_filesystem_error_message(e));
return false;
}
}
}
UninterruptibleSleep(std::chrono::milliseconds{100});
}
}
void BerkeleyDatabase::Flush()
{
if (!IsDummy()) {
env->Flush(false);
}
}
void BerkeleyDatabase::Close()
{
if (!IsDummy()) {
env->Flush(true);
}
}
void BerkeleyDatabase::ReloadDbEnv()
{
if (!IsDummy()) {
env->ReloadDbEnv();
}
}
bool BerkeleyBatch::StartCursor()
{
assert(!m_cursor);
if (!pdb)
return false;
int ret = pdb->cursor(nullptr, &m_cursor, 0);
return ret == 0;
}
bool BerkeleyBatch::ReadAtCursor(CDataStream& ssKey, CDataStream& ssValue, bool& complete)
{
complete = false;
if (m_cursor == nullptr) return false;
// Read at cursor
SafeDbt datKey;
SafeDbt datValue;
int ret = m_cursor->get(datKey, datValue, DB_NEXT);
if (ret == DB_NOTFOUND) {
complete = true;
}
if (ret != 0)
return false;
else if (datKey.get_data() == nullptr || datValue.get_data() == nullptr)
return false;
// Convert to streams
ssKey.SetType(SER_DISK);
ssKey.clear();
ssKey.write((char*)datKey.get_data(), datKey.get_size());
ssValue.SetType(SER_DISK);
ssValue.clear();
ssValue.write((char*)datValue.get_data(), datValue.get_size());
return true;
}
void BerkeleyBatch::CloseCursor()
{
if (!m_cursor) return;
m_cursor->close();
m_cursor = nullptr;
}
bool BerkeleyBatch::TxnBegin()
{
if (!pdb || activeTxn)
return false;
DbTxn* ptxn = env->TxnBegin();
if (!ptxn)
return false;
activeTxn = ptxn;
return true;
}
bool BerkeleyBatch::TxnCommit()
{
if (!pdb || !activeTxn)
return false;
int ret = activeTxn->commit(0);
activeTxn = nullptr;
return (ret == 0);
}
bool BerkeleyBatch::TxnAbort()
{
if (!pdb || !activeTxn)
return false;
int ret = activeTxn->abort();
activeTxn = nullptr;
return (ret == 0);
}
std::string BerkeleyDatabaseVersion()
{
return DbEnv::version(nullptr, nullptr, nullptr);
}
bool BerkeleyBatch::ReadKey(CDataStream&& key, CDataStream& value)
{
if (!pdb)
return false;
SafeDbt datKey(key.data(), key.size());
SafeDbt datValue;
int ret = pdb->get(activeTxn, datKey, datValue, 0);
if (ret == 0 && datValue.get_data() != nullptr) {
value.write((char*)datValue.get_data(), datValue.get_size());
return true;
}
return false;
}
bool BerkeleyBatch::WriteKey(CDataStream&& key, CDataStream&& value, bool overwrite)
{
if (!pdb)
return true;
if (fReadOnly)
assert(!"Write called on database in read-only mode");
SafeDbt datKey(key.data(), key.size());
SafeDbt datValue(value.data(), value.size());
int ret = pdb->put(activeTxn, datKey, datValue, (overwrite ? 0 : DB_NOOVERWRITE));
return (ret == 0);
}
bool BerkeleyBatch::EraseKey(CDataStream&& key)
{
if (!pdb)
return false;
if (fReadOnly)
assert(!"Erase called on database in read-only mode");
SafeDbt datKey(key.data(), key.size());
int ret = pdb->del(activeTxn, datKey, 0);
return (ret == 0 || ret == DB_NOTFOUND);
}
bool BerkeleyBatch::HasKey(CDataStream&& key)
{
if (!pdb)
return false;
SafeDbt datKey(key.data(), key.size());
int ret = pdb->exists(activeTxn, datKey, 0);
return ret == 0;
}
void BerkeleyDatabase::AddRef()
{
LOCK(cs_db);
if (m_refcount < 0) {
m_refcount = 1;
} else {
m_refcount++;
}
}
void BerkeleyDatabase::RemoveRef()
{
LOCK(cs_db);
m_refcount--;
if (env) env->m_db_in_use.notify_all();
}
std::unique_ptr<DatabaseBatch> BerkeleyDatabase::MakeBatch(const char* mode, bool flush_on_close)
{
return MakeUnique<BerkeleyBatch>(*this, mode, flush_on_close);
}
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